Two types of shafts dominate the golf club shaft market. The first type of shaft is made entirely of metal such as high strength alloy steel. The second type of shaft is made entirely of a composite such as graphite.
Metal shafts are generally regarded as being relatively heavy but provide high torsional stiffness. This results in a playability which yields accurate ball control and good feel but may limit club head speed and hence distance. It can also be made difficult to obtain a high tip flexibility with metal shafts compared to composite shafts which can compromise ball trajectory.
Composite shafts are generally regarded as being relatively light with more flexible tips which can result in a playability which yields higher club head speed and more distance as well as a higher ball trajectory. However, because composite shafts are not very torsionally stiff, composite shafts are also regarded as being somewhat limited in terms of accurate ball control and feel.
To take advantage of the separate benefits of metal and composite shafts while minimizing their deficiencies, a multiple material golf club shaft has recently been introduced to the market. A multiple material shaft is made partially of metal and partially of composite. In other words, a first portion of the shaft is formed of metal, a second portion of the shaft is made of composite, and the two portions are coupled together.
Multiple material shafts are generally regarded as being light weight and resistant to torque. This enables the generation of more club head speed than an all metal shaft and with better accuracy than an all composite shaft. Because club head speed is highly desirable for long irons with low lofts, and accuracy is highly desirable for short irons with high lofts, and a compromise of club head speed and accuracy is highly desirable for middle irons with medium lofts, it would be desirable to provide a golf club set which maximizes these shaft characteristics across the set.